Efficacy of bone marrow cytologic evaluations in detecting occult cancellous invasion

Abstract

Objectives/hypothesis: Determine the accuracy of bone marrow cytologic evaluations in detecting occult cancellous invasion by squamous cell carcinomas (SCCa) beyond the original margins of bone resection that would have gone undetected without the use of intraoperative bone-marrow margin analysis.

Study design: Retrospective single institution cohort study.

Methods: Retrospective chart review of imaging, clinical, pathological, and follow-up data of 51 patients who underwent mandibular resections with intraoperative bone-marrow cytologic evaluation. The accuracy of bone marrow cytologic evaluations to predict final bone margins was calculated. Five-year survival rates were determined.

Results: The accuracy of bone marrow cytologic evaluations in detecting occult cancellous invasion by SCCa beyond the original margins of bone resection was 100%. Twelve percent (6/51) were found to have positive bone margins on cytology and were re-resected to obtain clear margins. Patients with a prior history of radiation had a significantly higher incidence of initially positive bone-marrow margins (P = 0.03). The patients with initially positive bone-margins did not have a significantly different prognosis than the patients with initially negative bone-marrow margins.

Conclusion: 1) The consistent use of intraoperative bone-marrow cytologic evaluation, when applicable, will improve the ability to obtain clear bone margins. 2) Patients with a history of prior radiation therapy have a significantly higher risk of having occult cancellous invasion of SCCa beyond the original margins of bone resection. 3) The prognosis of patients with initially positive bone-marrow margins is not significantly different than patients with initially negative bone-marrow margins.

Level of evidence: 4.

Keywords: Oral cancer; bone marrow; cancellous bone; cytologic evaluation; cytology; frozen sections; history of radiation; mandible; mandibular invasion; margins; radiation; squamous cell carcinoma.